An analysis of tube drawing process used to produce squared sections from round tubes through FE simulation and response surface methodology

Tube drawing process is an attractive manufacturing technique in automobile, medical, and aerospace industries. The quality of fabricated tubes is highly affected by drawing parameters, e.g., die geometry, material properties, friction conditions, and drawing ratio. In the present study, an extensive attempt has been made to find optimal combinations of drawing parameters, i.e., die angle, friction coefficient, tube entrance velocity, and deformation length regarding minimum drawing force and dimensional error as well as maximum linear and peripheral thickness distributions. A combination of finite element model, validated through trial experiments, and face-centered central composite design was used to design a matrix. Then, response surface methodology (RSM) was used to correlate empirical relationships between process factors and responses. The developed RSM models were then used to find the effects of tube drawing parameters on the mentioned performances. RSM was used further for the selection of optimum process parameters to achieve the desired quality regarding tube drawing performance in producing squared sections from round tubes. The results showed that to attain desired quality characteristics, the die angle of 7.5°, deformation length of 3 mm, friction coefficient of 0.3, and entrance velocity of 5 mm/min should be selected. A comparison between the optimal results and those derived from finite element (FE) model showed that the proposed approach would be able to predict optimal drawing process combinations with a high degree of accuracy.